Defines "bets or wagers" to include bets for contests, sporting events, games predominantly subject to chance, and lotteries. Excludes from such definition: (1) activities governed by securities laws; (2) transactions under the Commodity Exchange Act; (3) over-the-counter derivative instruments; (4) contracts of indemnity or guarantee; (5) contracts for life, health, or accident insurance; and (6) reward programs or contests conducted by businesses.

(Sec. 3) Modifies existing prohibitions against interstate gambling to prohibit the use of a communication facility to transmit: (1) bets or wagers; (2) information assisting in the placing of bets or wagers; or (3) a communication that entitles the recipient to receive money or credit as a result of bets or wagers or for information assisting in the placing of bets or wagers.

Prohibits any individual from accepting, in connection with the placing of bets or wagers to or from the United States: (1) credit, or the proceeds of credit; (2) electronic funds transfers; (3) checks, drafts, or similar instruments; or (4) the proceeds of any other form of financial transaction as prescribed by Treasury regulations.

Imposes a fine and/or prison term of up to five years for violations.

Requires any common carrier that receives a notice of a violation of this Act by one of its communication facilities to discontinue or refuse service to such facility. Grants such common carrier immunity from liability for discontinuing or refusing such service.

(Sec. 4) Authorizes appropriations to the Department of Justice in FY2007-FY2010 for investigations and prosecutions of unlawful Internet gambling.

(Sec. 5) Declares that nothing in this Act may be construed to prohibit any activity allowed under the Interstate Horseracing Act or to preempt any state law prohibiting gambling.

(Sec. 6) Expresses the sense of Congress that this Act does not address the legality of certain horse racing activities under federal law.